Boceprevir for untreated chronic HCV genotype 1 infection

BACKGROUND

Peginterferon-ribavirin therapy is the current standard of care for chronic infection with hepatitis C virus (HCV). The rate of sustained virologic response has been below 50% in cases of HCV genotype 1 infection. Boceprevir, a potent oral HCV-protease inhibitor, has been evaluated as an additional treatment in phase 1 and phase 2 studies.

METHODS

We conducted a double-blind study in which previously untreated adults with HCV genotype 1 infection were randomly assigned to one of three groups. In all three groups, peginterferon alfa-2b and ribavirin were administered for 4 weeks (the lead-in period). Subsequently, group 1 (the control group) received placebo plus peginterferon-ribavirin for 44 weeks; group 2 received boceprevir plus peginterferon-ribavirin for 24 weeks, and those with a detectable HCV RNA level between weeks 8 and 24 received placebo plus peginterferon-ribavirin for an additional 20 weeks; and group 3 received boceprevir plus peginterferon-ribavirin for 44 weeks. Nonblack patients and black patients were enrolled and analyzed separately.

RESULTS

A total of 938 nonblack and 159 black patients were treated. In the nonblack cohort, a sustained virologic response was achieved in 125 of the 311 patients (40%) in group 1, in 211 of the 316 patients (67%) in group 2 (P<0.001), and in 213 of the 311 patients (68%) in group 3 (P<0.001). In the black cohort, a sustained virologic response was achieved in 12 of the 52 patients (23%) in group 1, in 22 of the 52 patients (42%) in group 2 (P=0.04), and in 29 of the 55 patients (53%) in group 3 (P=0.004). In group 2, a total of 44% of patients received peginterferon-ribavirin for 28 weeks. Anemia led to dose reductions in 13% of controls and 21% of boceprevir recipients, with discontinuations in 1% and 2%, respectively.

CONCLUSIONS

The addition of boceprevir to standard therapy with peginterferon-ribavirin, as compared with standard therapy alone, significantly increased the rates of sustained virologic response in previously untreated adults with chronic HCV genotype 1 infection. The rates were similar with 24 weeks and 44 weeks of boceprevir. (Funded by Schering-Plough [now Merck]; SPRINT-2 ClinicalTrials.gov number, NCT00705432.).

Oral Nirmatrelvir for High-Risk, Nonhospitalized Adults with Covid-19

BACKGROUND

Nirmatrelvir is an orally administered severe acute respiratory syndrome coronavirus 2 main protease (Mpro) inhibitor with potent pan-human-coronavirus activity in vitro.

METHODS

We conducted a phase 2-3 double-blind, randomized, controlled trial in which symptomatic, unvaccinated, nonhospitalized adults at high risk for progression to severe coronavirus disease 2019 (Covid-19) were assigned in a 1:1 ratio to receive either 300 mg of nirmatrelvir plus 100 mg of ritonavir (a pharmacokinetic enhancer) or placebo every 12 hours for 5 days. Covid-19-related hospitalization or death from any cause through day 28, viral load, and safety were evaluated.

RESULTS

A total of 2246 patients underwent randomization; 1120 patients received nirmatrelvir plus ritonavir (nirmatrelvir group) and 1126 received placebo (placebo group). In the planned interim analysis of patients treated within 3 days after symptom onset (modified intention-to treat population, comprising 774 of the 1361 patients in the full analysis population), the incidence of Covid-19-related hospitalization or death by day 28 was lower in the nirmatrelvir group than in the placebo group by 6.32 percentage points (95% confidence interval [CI], -9.04 to -3.59; P<0.001; relative risk reduction, 89.1%); the incidence was 0.77% (3 of 389 patients) in the nirmatrelvir group, with 0 deaths, as compared with 7.01% (27 of 385 patients) in the placebo group, with 7 deaths. Efficacy was maintained in the final analysis involving the 1379 patients in the modified intention-to-treat population, with a difference of -5.81 percentage points (95% CI, -7.78 to -3.84; P<0.001; relative risk reduction, 88.9%). All 13 deaths occurred in the placebo group. The viral load was lower with nirmatrelvir plus ritonavir than with placebo at day 5 of treatment, with an adjusted mean difference of -0.868 log10 copies per milliliter when treatment was initiated within 3 days after the onset of symptoms. The incidence of adverse events that emerged during the treatment period was similar in the two groups (any adverse event, 22.6% with nirmatrelvir plus ritonavir vs. 23.9% with placebo; serious adverse events, 1.6% vs. 6.6%; and adverse events leading to discontinuation of the drugs or placebo, 2.1% vs. 4.2%). Dysgeusia (5.6% vs. 0.3%) and diarrhea (3.1% vs. 1.6%) occurred more frequently with nirmatrelvir plus ritonavir than with placebo.

CONCLUSIONS

Treatment of symptomatic Covid-19 with nirmatrelvir plus ritonavir resulted in a risk of progression to severe Covid-19 that was 89% lower than the risk with placebo, without evident safety concerns. (Supported by Pfizer; ClinicalTrials.gov number, NCT04960202.).

Boceprevir for previously treated chronic HCV genotype 1 infection

BACKGROUND

In patients with chronic infection with hepatitis C virus (HCV) genotype 1 who do not have a sustained response to therapy with peginterferon-ribavirin, outcomes after retreatment are suboptimal. Boceprevir, a protease inhibitor that binds to the HCV nonstructural 3 (NS3) active site, has been suggested as an additional treatment.

METHODS

To assess the effect of the combination of boceprevir and peginterferon-ribavirin for retreatment of patients with chronic HCV genotype 1 infection, we randomly assigned patients (in a 1:2:2 ratio) to one of three groups. In all three groups, peginterferon alfa-2b and ribavirin were administered for 4 weeks (the lead-in period). Subsequently, group 1 (control group) received placebo plus peginterferon-ribavirin for 44 weeks; group 2 received boceprevir plus peginterferon-ribavirin for 32 weeks, and patients with a detectable HCV RNA level at week 8 received placebo plus peginterferon-ribavirin for an additional 12 weeks; and group 3 received boceprevir plus peginterferon-ribavirin for 44 weeks.

RESULTS

A total of 403 patients were treated. The rate of sustained virologic response was significantly higher in the two boceprevir groups (group 2, 59%; group 3, 66%) than in the control group (21%, P<0.001). Among patients with an undetectable HCV RNA level at week 8, the rate of sustained virologic response was 86% after 32 weeks of triple therapy and 88% after 44 weeks of triple therapy. Among the 102 patients with a decrease in the HCV RNA level of less than 1 log(10) IU per milliliter at treatment week 4, the rates of sustained virologic response were 0%, 33%, and 34% in groups 1, 2, and 3, respectively. Anemia was significantly more common in the boceprevir groups than in the control group, and erythropoietin was administered in 41 to 46% of boceprevir-treated patients and 21% of controls.

CONCLUSIONS

The addition of boceprevir to peginterferon-ribavirin resulted in significantly higher rates of sustained virologic response in previously treated patients with chronic HCV genotype 1 infection, as compared with peginterferon-ribavirin alone. (Funded by Schering-Plough [now Merck]; HCV RESPOND-2 ClinicalTrials.gov number, NCT00708500.).

Cardiovascular and Renal Outcomes with Efpeglenatide in Type 2 Diabetes

BACKGROUND

Four glucagon-like peptide-1 (GLP-1) receptor agonists that are structurally similar to human GLP-1 have been shown to reduce the risk of adverse cardiovascular events among persons with type 2 diabetes. The effect of an exendin-based GLP-1 receptor agonist, efpeglenatide, on cardiovascular and renal outcomes in patients with type 2 diabetes who are also at high risk for adverse cardiovascular events is uncertain.

METHODS

In this randomized, placebo-controlled trial conducted at 344 sites across 28 countries, we evaluated efpeglenatide in participants with type 2 diabetes and either a history of cardiovascular disease or current kidney disease (defined as an estimated glomerular filtration rate of 25.0 to 59.9 ml per minute per 1.73 m² of body-surface area) plus at least one other cardiovascular risk factor. Participants were randomly assigned in a 1:1:1 ratio to receive weekly subcutaneous injections of efpeglenatide at a dose of 4 or 6 mg or placebo. Randomization was stratified according to use of sodium-glucose cotransporter 2 inhibitors. The primary outcome was the first major adverse cardiovascular event (MACE; a composite of nonfatal myocardial infarction, nonfatal stroke, or death from cardiovascular or undetermined causes).

RESULTS

A total of 4076 participants were enrolled; 2717 were assigned to receive efpeglenatide and 1359 to receive placebo. During a median follow-up of 1.81 years, an incident MACE occurred in 189 participants (7.0%) assigned to receive efpeglenatide (3.9 events per 100 person-years) and 125 participants (9.2%) assigned to receive placebo (5.3 events per 100 person-years) (hazard ratio, 0.73; 95% confidence interval [CI], 0.58 to 0.92; P<0.001 for noninferiority; P = 0.007 for superiority). A composite renal outcome event (a decrease in kidney function or macroalbuminuria) occurred in 353 participants (13.0%) assigned to receive efpeglenatide and in 250 participants (18.4%) assigned to receive placebo (hazard ratio, 0.68; 95% CI, 0.57 to 0.79; P<0.001). Diarrhea, constipation, nausea, vomiting, or bloating occurred more frequently with efpeglenatide than with placebo.

CONCLUSIONS

In this trial involving participants with type 2 diabetes who had either a history of cardiovascular disease or current kidney disease plus at least one other cardiovascular risk factor, the risk of cardiovascular events was lower among those who received weekly subcutaneous injections of efpeglenatide at a dose of 4 or 6 mg than among those who received placebo. (Funded by Sanofi; AMPLITUDE-O ClinicalTrials.gov number, NCT03496298.).

Triple therapy in treatment-experienced patients with HCV-cirrhosis in a multicentre cohort of the French Early Access Programme (ANRS CO20-CUPIC) - NCT01514890

BACKGROUND & AIMS

In phase III trials, the safety profile of triple therapy (pegylated interferon/ribavirin with boceprevir or telaprevir) seems to be similar in HCV treatment-experienced cirrhotic and non-cirrhotic patients, but few cirrhotics were included. We report the week 16 safety and efficacy analysis in a cohort of compensated cirrhotics treated in the French Early Access Programme.

METHODS

674 genotype 1 patients, prospectively included, received 48 weeks of triple therapy. The analysis is restricted to 497 patients reaching week 16.

RESULTS

A high incidence of serious adverse events (40.0%), and of death and severe complications (severe infection or hepatic decompensation) (6.4%), and a difficult management of anaemia (erythropoietin and transfusion use in 50.7% and 12.1%) were observed. Independent predictors of anaemia < 8 g/dl or blood transfusion were: female gender (OR 2.19, 95% CI 1.11-4.33, p=0.024), no lead-in phase (OR 2.25, 95% CI 1.15-4.39, p=0.018), age ≥ 65 years (OR 3.04, 95% CI 1.54-6.02, p=0.0014), haemoglobin level (≤ 12 g/dl for females, ≤ 13 g/dl for males) (OR 5.30, 95% CI 2.49-11.5, p=0.0001). Death or severe complications were related to platelets count ≤ 100,000/mm(3) (OR 3.11, 95% CI 1.30-7.41, p=0.0105) and albumin <35 g/dl (OR 6.33, 95% CI 2.66-15.07, p=0.0001), with a risk of 44.1% in patients with both. However, the on-treatment virological response was high.

CONCLUSIONS

The safety profile was poor and patients with platelet count ≤ 100,000/mm(3) and serum albumin <35 g/L should not be treated with the triple therapy.

Effectiveness of telaprevir or boceprevir in treatment-experienced patients with HCV genotype 1 infection and cirrhosis

BACKGROUND & AIMS

We investigated the effectiveness of the protease inhibitors peginterferon and ribavirin in treatment-experienced patients with hepatitis C virus (HCV) genotype 1 infection and cirrhosis.

METHODS

In the Compassionate Use of Protease Inhibitors in Viral C Cirrhosis study, 511 patients with HCV genotype 1 infection and compensated cirrhosis who did not respond to a prior course of peginterferon and ribavirin (44.3% relapsers or patients with viral breakthrough, 44.8% partial responders, and 8.0% null responders) were given either telaprevir (n = 299) or boceprevir (n = 212) for 48 weeks. We assessed percentages of patients with sustained viral responses 12 weeks after therapy and safety. This observational study did not allow for direct comparison of the 2 regimens.

RESULTS

Among patients given telaprevir, 74.2% of relapsers, 40.0% of partial responders, and 19.4% of null responders achieved SVR12. Among those given boceprevir, 53.9% of relapsers, 38.3% of partial responders, and none of the null responders achieved SVR12. In multivariate analysis, factors associated with SVR12 included prior response to treatment response, no lead-in phase, HCV subtype 1b (vs 1a), and baseline platelet count greater than 100,000/mm(3). Severe adverse events occurred in 49.9% of cases, including liver decompensation, severe infections in 10.4%, and death in 2.2%. In multivariate analysis, baseline serum albumin level less than 35 g/L and baseline platelet counts of 100,000/mm(3) or less predicted severe side effects or death.

CONCLUSIONS

Relatively high percentages of real-life, treatment-experienced patients with HCV genotype 1 infection and cirrhosis respond to the combination of peginterferon and ribavirin with telaprevir or boceprevir. However, side effects are frequent and often severe. Baseline levels of albumin and platelet counts can be used to guide treatment decisions. ClinicalTrials.gov number: NCT01514890.

The metabolism of proline as microenvironmental stress substrate

Proline, a unique proteogenic secondary amino acid, has its own metabolic system with special features. Recent findings defining the regulation of this system led us to propose that proline is a stress substrate in the microenvironment of inflammation and tumorigenesis. The criteria for proline as a stress substrate are: 1) the enzymes utilizing proline respond to stress signaling; 2) there is a large, mobilizable pool of proline; and 3) the metabolism of proline serves special stress functions. Studies show that the proline-utilizing enzyme, proline oxidase (POX)/proline dehydrogenase (PRODH), responds to genotoxic, inflammatory, and nutrient stress. Proline as substrate is stored as collagen in extracellular matrix, connective tissue, and bone and it is rapidly released from this reservoir by the sequential action of matrix metalloproteinases, peptidases, and prolidase. Special functions include the use of proline by POX/PRODH to generate superoxide radicals that initiate apoptosis by intrinsic and extrinsic pathways. Under conditions of nutrient stress, proline is an energy source. It provides carbons for the tricarboxylic acid cycle and also participates in the proline cycle. The latter, catalyzed by mitochondrial POX and cytosolic pyrroline-5-carboxylate reductase, shuttles reducing potential from the pentose phosphate pathway into mitochondria to generate ATP and oxidizing potential to activate the cytosolic pentose phosphate pathway.

Glecaprevir/pibrentasvir for 8 weeks in treatment-naïve patients with chronic HCV genotypes 1-6 and compensated cirrhosis: The EXPEDITION-8 trial

BACKGROUND & AIMS

Eight-week glecaprevir/pibrentasvir leads to high rates of sustained virological response at post-treatment week 12 (SVR12) across HCV genotypes (GT) 1-6 in treatment-naïve patients without cirrhosis. We evaluated glecaprevir/pibrentasvir once daily for 8 weeks in treatment-naïve patients with compensated cirrhosis.

METHODS

EXPEDITION-8 was a single-arm, multicenter, phase IIIb trial. The primary and key secondary efficacy analyses were to compare the lower bound of the 95% CI of the SVR12 rate in i) patients with GT1,2,4-6 in the per protocol (PP) population, ii) patients with GT1,2,4-6 in the intention-to-treat (ITT) population, iii) patients with GT1-6 in the PP population, and iv) patients with GT1-6 in the ITT population, to pre-defined efficacy thresholds based on historical SVR12 rates for 12 weeks of glecaprevir/pibrentasvir in the same populations. Safety was also assessed.

RESULTS

A total of 343 patients were enrolled. Most patients were male (63%), white (83%), and had GT1 (67%). The SVR12 rate in patients with GT1-6 was 99.7% (n/N = 334/335; 95%CI 98.3-99.9) in the PP population and 97.7% (n/N = 335/343; 95% CI 96.1-99.3) in the ITT population. All primary and key secondary efficacy analyses were achieved. One patient (GT3a) experienced relapse (0.3%) at post-treatment week 4. Common adverse events (≥5%) were fatigue (9%), pruritus (8%), headache (8%), and nausea (6%). Serious adverse events (none related) occurred in 2% of patients. No adverse event led to study drug discontinuation. Clinically significant laboratory abnormalities were infrequent.

CONCLUSIONS

Eight-week glecaprevir/pibrentasvir was well tolerated and led to a similarly high SVR12 rate as the 12-week regimen in treatment-naïve patients with chronic HCV GT1-6 infection and compensated cirrhosis.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03089944.

LAY SUMMARY

This study was the first to evaluate an 8-week direct-acting antiviral (DAA) regimen active against all major types of hepatitis C virus (HCV) in untreated patients with compensated cirrhosis. High virological cure rates were achieved with glecaprevir/pibrentasvir across HCV genotypes 1-6, and these high cure rates did not depend on any patient or viral characteristics present before treatment. This may simplify care and allow non-specialist healthcare professionals to treat these patients, contributing to global efforts to eliminate HCV.

Behavioral and neurochemical effects of proline

Proline is an amino acid with an essential role for primary metabolism and physiologic functions. Hyperprolinemia results from the deficiency of specific enzymes for proline catabolism, leading to tissue accumulation of this amino acid. Hyperprolinemic patients can present neurological symptoms and brain abnormalities, whose aetiopathogenesis is poorly understood. This review addresses some of the findings obtained, mainly from animal studies, indicating that high proline levels may be associated to neuropathophysiology of some disorders. In this context, it has been suggested that energy metabolism deficit, Na(+),K(+)-ATPase, kinase creatine, oxidative stress, excitotoxicity, lipid content, as well as purinergic and cholinergic systems are involved in the effect of proline on brain damage and spatial memory deficit. The discussion focuses on the relatively low antioxidant defenses of the brain and the vulnerability of neural tissue to reactive species. This offers new perspectives for potential therapeutic strategies for this condition, which may include the early use of appropriate antioxidants as a novel adjuvant therapy, besides the usual treatment based on special diets poor in proline.

A US multicenter study of hepatitis C treatment of liver transplant recipients with protease-inhibitor triple therapy

BACKGROUND & AIMS

NS3/4A protease inhibitors, boceprevir or telaprevir, combined with peginterferon and ribavirin was the standard treatment for HCV genotype 1 and remains the only available direct antiviral drug based therapy in some countries. Efficacy and safety data in liver transplant recipients are limited.

METHODS

This was a retrospective cohort study of 81 patients with genotype 1 HCV treated with boceprevir (10%) or telaprevir (90%) plus peginterferon and ribavirin at 6 US transplant centers (53% stage 3-4/4 fibrosis, 57% treatment experienced). The primary end point was undetectable HCV RNA 12 weeks after treatment completion (SVR12).

RESULTS

The intent-to-treat SVR12 rate was 63% (51/81). Patients with an extended rapid virologic response, (undetectable HCV RNA at 4 and 12 weeks after starting boceprevir or telaprevir), had a higher rate of SVR12 than all other patients (85% vs. 15%, p<0.001). Adverse effects were common; 21% of patients experienced hemoglobin <8g/dl and 57% required blood transfusions during the first 16 weeks. Twenty seven percent were hospitalized and 9% died; all were liver-related.

CONCLUSIONS

The addition of boceprevir or telaprevir to peginterferon and ribavirin yields SVR12 of 63% in liver transplant recipients with genotype 1 recurrent HCV, despite a high prevalence of advanced fibrosis and prior non-response to peginterferon and ribavirin. Rapid virologic response predicted a high likelihood of SVR. Despite a doubling of SVR rates, poor tolerability and high rates of adverse events were frequent and pose barriers to its widespread application.

Intravenous immunoglobulins: in-depth review of excipients and acute kidney injury risk

BACKGROUND

Used in a variety of approved and off-label indications, there are several intravenous immunoglobulin (IVIG) preparations available which differ in the excipients (e.g. sucrose, glucose, maltose, D-sorbitol, glycine or L-proline) used to stabilize the protein in the solution. A very rare, but severe adverse drug reaction (ADR) reported with sucrose-stabilized IVIGs, acute renal failure, is well established, but the relative risks with sucrose-free IVIGs are unknown.

METHODS

Medline and Embase were searched for published data on ADRs involving the kidney, and DrugCite, a public database of >4,000,000 ADRs from the USA, was also searched. Renal impairment-associated ADRs and categories were summarized.

RESULTS

Compared with sucrose-containing IVIGs, reports of ADRs involving the kidney were relatively rare with sucrose-free IVIGs: 12 cases were published prior to February 28, 2012; incidences reported in DrugCite were also relatively low and similar among sucrose-free preparations. The incidence of hemolysis-related ADRs, a potential cause of secondary acute renal impairment, was higher with glycine- and L-proline-stabilized IVIGs. Reported incidences of renal impairment with sucrose-free IVIGs are similar between products and much lower than with sucrose-stabilized IVIGs.

CONCLUSIONS

It is recommended that the choice of IVIG should be guided by the patient's medical history, present comorbidities and concomitant medications. Prospective studies with inclusion of creatinine values, as well as rigorous reporting of cases in the literature and/or via pharmacovigilance systems, are imperative to better define patient profiles.

Peg-IFNα/ribavirin/protease inhibitor combination in hepatitis C virus associated mixed cryoglobulinemia vasculitis: results at week 24

BACKGROUND

The standard-of-care treatment of patients with hepatitis C virus (HCV)-mixed cryoglobulinemia (MC) vasculitis includes pegylated interferon α (PegIFN)-α plus ribavirin and/or rituximab. About 30-40% of patients are non-responders or relapsers to such combination.

OBJECTIVE

To analyse the safety and efficacy of Peg-IFNα/ribavirin/protease inhibitor combination in HCV-MC vasculitis.

PATIENTS AND METHODS

Open-label, prospective, cohort study including 23 patients with HCV-MC vasculitis. Peg-IFNα/ribavirin was associated to telaprevir (375 mg three times daily, for 12 weeks, (n=15)) or boceprevir (800 mg three times daily, for 44 weeks, (n=8)) for 48 weeks.

RESULTS

The median age was 59 (52.5-66) years, with 48.8% women. Thirteen patients (56.5%) were complete clinical responders, and 10 (43.5%) were partial responders at week 24. The virological response (ie, HCV RNA negativation) was of 69.6% at week 24 (p=0.005). The cryoglobulin level decreased from 0.44 to 0.06 g/l (p=0.0006) and the C4 level increased from 0.09 to 0.15 g/l (p=0.045). Grades 3 and 4 adverse events (mainly anaemia, neutropenia and thrombocytopenia) were observed in 10 cases (43.5%). Twenty patients (87%) received erythropoietin, 9 (39.1%) had red cell transfusion, and 2 (8.7%) had granulocyte stimulating agents. Antiviral therapy discontinuation was required in 8 (34.7%) patients for virological non-response (n=5), virological relapse (n=2) and depression (n=1).

CONCLUSIONS

Peg-IFNα/ribavirin/protease inhibitor combination seems highly effective in HCV-MC. Such therapeutic regimen should be administered cautiously considering the high rate of side effects.

Anemia during treatment with peginterferon Alfa-2b/ribavirin and boceprevir: Analysis from the serine protease inhibitor therapy 2 (SPRINT-2) trial

Boceprevir (BOC) added to peginterferon alfa-2b (PegIFN) and ribavirin (RBV) significantly increases sustained virologic response (SVR) rates over PegIFN/RBV alone in previously untreated adults with chronic hepatitis C genotype 1. We evaluate the relationship of incident anemia with triple therapy. A total of 1,097 patients received a 4-week lead-in of PegIFN/RBV followed by: (1) placebo plus PegIFN/RBV for 44 weeks (PR48); (2) BOC plus PegIFN/RBV using response-guided therapy (BOC/RGT); and (3) BOC plus PegIFN/RBV for 44 weeks (BOC/PR48). The management of anemia (hemoglobin [Hb]<10 g/dL) included RBV dose reduction and/or erythropoietin (EPO) use. A total of 1,080 patients had ≥1 Hb measurement during treatment. The incidence of anemia was 50% in the BOC arms combined (363/726) and 31% in the PR48 arm (108/354, P<0.001). Among BOC recipients, lower baseline Hb and creatinine clearance were associated with incident anemia. In the BOC-containing arms, anemia was managed by the site investigators as follows: EPO without RBV dose reduction, 38%; RBV dose reduction without EPO, 8%; EPO with RBV dose reduction, 40%; and neither RBV dose reduction nor EPO, 14%. SVR rates were not significantly affected by management strategy (70%-74%), and overall patients with anemia had higher rates of SVR than those who did not develop anemia (58%). Serious and life-threatening adverse events (AEs) and discontinuations due to AEs among BOC-treated patients did not differ by EPO use.

CONCLUSION

With BOC/PR therapy, SVR rates in patients with incident anemia were higher than nonanemic patients and did not vary significantly according to the investigator-selected approach for anemia management. Prospective studies are needed to confirm this observation.

Phase 2 study of danicopan in patients with paroxysmal nocturnal hemoglobinuria with an inadequate response to eculizumab

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by uncontrolled terminal complement activation and subsequent intravascular hemolysis (IVH). C5 inhibitors prevent membrane attack complex formation, but patients may experience extravascular hemolysis (EVH) and continue to require blood transfusions. Danicopan, an oral proximal complement inhibitor of alternative pathway factor D (FD), is designed to control IVH and EVH. In a phase 2 dose-finding trial, eculizumab-treated transfusion-dependent patients with PNH (n = 12) received danicopan, 100 to 200 mg thrice daily, in addition to their eculizumab regimen for 24 weeks. End points included hemoglobin (Hgb) change vs baseline at week 24 (primary), reduction in blood transfusions, and patient-reported outcomes. Safety, tolerability, and pharmacokinetics/pharmacodynamics were measured. Twelve patients received ≥1 danicopan dose; 1 patients discontinued from a serious adverse event deemed unlikely related to danicopan. Eleven patients completed the 24-week treatment period. Addition of danicopan resulted in a mean Hgb increase of 2.4 g/dL at week 24. In the 24 weeks prior to danicopan, 10 patients received 31 transfusions (50 units) compared with 1 transfusion (2 units) in 1 patient during the 24-week treatment period. Mean Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue score increased by 11 points from baseline to week 24. The most common adverse events were headache, cough, and nasopharyngitis. Addition of danicopan, a first-in-class FD inhibitor, led to a meaningful improvement in Hgb and reduced transfusion requirements in patients with PNH who were transfusion-dependent on eculizumab. These benefits were associated with improvement of FACIT-Fatigue. This trial was registered at www.clinicaltrials.gov as #NCT03472885.

Drug-drug interactions with oral anti-HCV agents and idiosyncratic hepatotoxicity in the liver transplant setting

Studies of boceprevir and telaprevir based antiviral therapy in liver transplant (LT) recipients with hepatitis C genotype 1 infection have demonstrated dramatic increases in tacrolimus, cyclosporine, and mTOR inhibitor exposure. In addition to empiric dose reductions, daily monitoring of immunosuppressant blood levels is required when initiating as well as discontinuing the protease inhibitors to maximize patient safety. Although improved suppression of HCV replication is anticipated, 20 to 40% of treated subjects have required early treatment discontinuation due to various adverse events including anemia (100%), infection (30%), nephrotoxicity (20%) and rejection (5 to 10%). Simeprevir and faldaprevir will likely have improved efficacy and safety profiles but potential drug interactions with other OATP1B1 substrates and unconjugated hyperbilirubinemia are expected. In contrast, sofosbuvir and daclatasvir based antiviral therapy are not expected to lead to clinically significant drug-drug interactions in LT recipients but confirmatory studies are needed. Liver transplant recipients may also be at increased risk of developing drug induced liver injury (DILI). Establishing a diagnosis of DILI in the transplant setting is very difficult with the variable latency, laboratory features and histopathological manifestations of hepatotoxicity associated with a given drug, the need to exclude competing causes of allograft injury, and the lack of an objective and verifiable confirmatory test. Nonetheless, a heightened awareness of the possibility of DILI is warranted in light of the large number of medications used in LT recipients and the potential adverse impact that DILI may have on patient outcomes.

Maximizing opportunities and avoiding mistakes in triple therapy for hepatitis C virus

Recently developed drugs and innovative strategies for the treatment of chronic infection with genotype 1 hepatitis C virus (HCV) have become the standard of care. The protease inhibitors telaprevir (Incivek) and boceprevir (Victrelis) are the first direct-acting antiviral (DAA) agents approved, and many more are being developed. These drugs substantially increased rates of sustained virologic response in treatment-naïve and -experienced patients, in conjunction with peginterferon and ribavirin (triple therapy), in phase 3 trials. The efficacy of triple therapy depends on appropriate selection of patients, although the population of patients that receive triple therapy could be expanded as the risk/benefit ratio improves. Attention to details that reflect the standard of care, such as appropriate dosing, anticipation of adverse effects, and strict adherence to stopping rules, will insure the success of these drugs and lead the way for new combination therapies.

Multicenter Experience with Boceprevir or Telaprevir to Treat Hepatitis C Recurrence after Liver Transplantation: When Present Becomes Past, What Lessons for Future?

Background and aims

First generation protease inhibitors (PI) with peg-interferon (PEG-IFN) and ribavirin (RBV) have been the only therapy available for hepatitis C virus (HCV) genotype 1 infection in most countries for 3 years. We have investigated the efficacy and tolerance of this triple therapy in transplanted patients experiencing a recurrence of HCV infection on the liver graft.

Patients

This cohort study enrolled 81 liver transplant patients (Male: 76%, mean age: 55.8±9.7 years) with severe HCV recurrence (F3 or F4: n = 34 (42%), treatment experienced: n = 44 (54%)), treated with boceprevir (n = 36; 44%) or telaprevir (n = 45; 56%). We assessed the percentages of patients with sustained virological responses 24 weeks after therapy (SVR24), and safety.

Results

The SVR24 rate was 47% (telaprevir: 42%; boceprevir: 53%, P = ns). At baseline, a normal bilirubin level (p = 0.0145) and albumin level >35g/L (p = 0.0372) and an initial RBV dosage of ≥800 mg/day (p = 0.0033) predicted SVR24. During treatment, achieving an early virological response after 12 weeks was the strongest independent factor to predict SVR24 (p<0.0001). A premature discontinuation of anti-HCV therapy due to a serious adverse event (SAE) was observed in 22 patients (27%). Hematological toxicity, infections and deaths were observed in 95%, 28% and 7% of patients, respectively. A history of post-LT antiviral therapy and thrombocytopenia (<50G/L) during treatment were both independent predictors of the occurrence of infections or SAE (p = 0.0169 and p = 0.011).

Conclusions

The use of first generation PI after liver transplantation enabled an SVR24 rate of 47% in genotype 1 patients, but induced a high rate of SAE. The identification of predictive factors for a response to treatment, and the occurrence of SAE, have enabled us to establish limits for the use of this anti-HCV therapy in the transplant setting.

First clinical study using HCV protease inhibitor danoprevir to treat COVID-19 patients

INTRODUCTION

As coronavirus disease 2019 (COVID-19) outbreak globally, repurposing approved drugs is emerging as important therapeutic options. Danoprevir boosted by ritonavir (Ganovo) is a potent hepatitis C virus (HCV) protease (NS3/4A) inhibitor, which was approved and marketed in China since 2018 to treat chronic hepatitis C patients.

METHODS

This is an open-label, single arm study evaluating the effects of danoprevir boosted by ritonavir on treatment naïve and experienced COVID-19 patients for the first time. Patients received danoprevir boosted by ritonavir (100 mg/100 mg, twice per day). The primary endpoint was the rate of composite adverse outcomes and efficacy was also evaluated.

RESULTS

The data showed that danoprevir boosted by ritonavir is safe and well tolerated in all patients. No patient had composite adverse outcomes during this study. After initiation of danoprevir/ritonavir treatment, the first negative reverse real-time PCR (RT-PCR) test occurred at a median of 2 days, ranging from 1 to 8 days, and the obvious absorption in CT scans occurred at a median 3 days, ranging from 2 to 4 days. After 4 to 12-day treatment of danoprevir boosted by ritonavir, all enrolled 11 patients were discharged from the hospital.

CONCLUSION

Our findings suggest that repurposing danoprevir for COVID-19 is a promising therapeutic option.